The invention relates to optical systems and methods for magnifying images or controlling the sizes of laser spots or optical images, and in particular to optical systems and methods employing rotating cylindrical lenses and/or mirrors.
Microscopes, image projectors, industrial laser optical systems, and various other optical systems have been used to control the sizes of images at a target location. Many such optical systems employ lenses and/or mirrors which are translated relative to each other along the optical axis of the system in order to control the output image size. In some systems, changing the size of the image alters the location of the plane at which the image is in focus. Moreover, some conventional systems can be relatively bulky, and require complex mechanical components.
The present invention provides an optical system comprising a first cylindrical optical element for receiving an input light beam, and a second cylindrical optical element positioned at a round spot location optically subsequent to the first cylindrical optical element. At least one of the cylindrical optical elements is rotatable about the optical axis so as to adjust an angle between the principal axes of the cylindrical optical elements to symmetrically scale a light beam spot at a target location.
Further provided is an optical method comprising: generating a symmetrically-scalable spot on a target positioned at a working location by passing a light beam sequentially through a first cylindrical optical element and a second cylindrical optical element, the second cylindrical optical element being separated from the first cylindrical optical element by a distance chosen such that an input beam forms a circular spot at the second cylindrical optical element after passing through the first cylindrical optical element; and symmetrically scaling the spot at the working location by adjusting an angle between a principal axis of the first cylindrical optical element and a principal axis of the second cylindrical optical element by rotating at least one of the first cylindrical optical element and the second cylindrical optical element.